Hot-plate apparatus for explosive-engines.



H. F. SHEPHERD.

HOT PLATE APPARATUS FOR EXPLOSIW. ENGINES.

APPLICATHJN FILED IULY 22.1918. mzmwzn mv 11.3919.

1,3 1 7, 900. .Patfinfm'l Oct. 7, 1919.

UNITED STATES PATENT OFFICE.

HAROLD F. SHEPHERD, 0F GROVEGI'IY, PENNSYLVANIA, ASSIGNOR 'I'O BESSEMER GAS ENGINE COMPANY, OF GROVE CITY, PENNSYLVANIA, A CORPORATION OF PENN- BYLVANIA.

HOT-PLATE APPARATUS FOR EXPLOBIVE-ENGINEB.

Specification of Letters Patent.

Patented Oct. '7, 1919.

Origipal application filed November 20, 1917, Serial No. 204,582. Divided and this application flied July 22, 1918. Serial No. 246,033. Renewed May 8, 1919. Serial No. 295,708.

To all whom it may concern:

Be it known that I, HAROLD F. SHEPHERD, a citizen ofthe United States, residing at Grove City, in the county of Mercer and State of Pennsylvania, have invented new and useful Improvements in Hot-Plate A.

aratus for Explosive-Engincs, of which t e lbllowing is a specification.

. This invention relates to hot plate apparatus for explosiye engines and consists in certain improvements in the construction thereof as willlliehereinafter fully described and pointed out inthe claims.

This application is a division of aplication Serial Number 204,532, filed y me Nov. 20, 1917, for improvements in hot plate apparatus in which the invention in its broader phase is claimed.

The invention is illustrated in the accompanying drawings as follows:

. Figure 1 shows a central section of the end of an explosion chamber of an explosive engine equipped with the hot plate apparatus.

Fig. 2 shows an elevation of an alternative construction of a hot plate apparatus.

1 marks the cylinder, 2 the explosion chamber, 3 the hot bulb operating at the end of the explosion chamber, 3 a. ring for securing the hot bulb in place and 4'. a startingfplug.

he starting plug comprises a hot plate in the form of a receptacle 5. The upper end of this receptacle is provided with a screw thread 6 which is inserted in a screwthreaded opening in the hot bulb. The receptacle contains a liquid 7 having a piedetermined desired vaporizing point. is vaporizing point may be accomplished from the nature of the material used so as to have the desired pre-dctemiined temperaliire at atmospheric pressure, or the pressure in the receptacle may be varied so as to vary the boiling or vaporizing point if desired. Ordinarlly mercury is used in the starting lug, this having a vaporizing point approxlmating that desired. If a slightly hlgher tem erature is desired this may be accomplis ed by subjecting the receptacle to a slight=pressure and closingI the receptacle by soldering. A water jac et 8 surrounds the outer end of the plug and is connected by the tubes 9 with the circulating system of the engine (not shown). This water jacket forms a condenser so that the vapor arising from the liquid when heated upon coming lIlllO contact with the upper walls of the receptacle adjacent to the water jacket is immediately condensed and the liquid so condensed is returned to the body of the liquid 7. The condenser is practically insulated from the liquid in that the va or in itself is not a good conductor of heat. he heat, however, 1s dissipated automatically through the particles of vapor actin on the condensing plate. At the same tune the temperature of the late from its direct contact with the liqui is maintained approximntely constant at the vaporizing point of the liquid.

In order to heat the plug for starting the engine an electric heating unit having a heating element 10 is used. This element is connected with the terminals 11 and 12 surrounded by an insulating coat 13 and a sheath 14. The heating unit, or element, is immersed in the liquid and heats the liquid to the vaporizing point and consequently heats-the plate so as to start the engine.

The liquid not only maintains the plate below a tern erature at which it can be in jured throug the excessive heat' incident to the explosions of the engine but it also protects the plate against excessive heating through the action of the electric heating element 10.

The plug is preferably directly opposite the fuel injecting nozzle 15.

In Fig. 2 I have shown an alternative construction wherein an air cooling wall 8 is substituted for the water jacket 8. Otherwise the construction is similar to that shown in Fig. 1.

What I claim as new is 1. In combination an explosion chamber of an explosive engine; means for introducing fuel to said chamber a liquid receptacle comprising a plate subjected to variations of tern erature incident to the explosions receptacle vaporizing at a pro-determined desired temperature; an electric heating element immersed in said liquid; and means for condensing and returning the vapor.

3. In combination an explosion chamber of an explosive engine; means for introducing fuel to said chamber; a liquid receptacle comprising a late in said chamber and acting on the uel; liquid in the receptacle vaporizin at or above the ignition temperature; an an electric heating element immersed in said liquid.

4. In combination an explosion chamber of an explosive engine; means for introducing fuel to said chamber; a liquid receptacle comprising a plate in said chamber and acting on the fuel; a liquid in the receptacle vaporizing at 01' above the ignition tempera- .ture; an electric heating element immersed in.said liquid; and means for condensing and returning the vapor.

5. In combination an explosion chamber of an explosive engine; means for introducing fuel to said chamber; a hot bulb by Wl'liOll said fuel is normally ignited; a liquid receptacle comprising a plate subjected to the explosions and acting on the fuel liquid in the receptacle vaporizing at or a ove ignition temperature; and an electric heating element immersed in said liquid.

6, A starting plug for explosive engines comprising a receptacle adapted to be inserted into an explosion chamber; a condenser arranged on the outer end of said plu and adapted to be arranged without said chamber; a liquid contained in said plug vaporizing at a pre-determined desiredtemperature; and an electric heating ele-' ment operating on said liquid.

7 A starting plug for explosive engines comprising a receptacle; a screw thread on said receptacle for securing the same to the walls of an explosion chamber; a condenser arrangcdon the receptacle and without the screw thread; a liquid contained in the receptacle having a vaporizing point at a predetermined desired temperature; and an electric heating element operating on said 'liquid.

In testimony whereof I have hereunto set my hand.

H. F. SHEPHERD. 

